Low Energy Challenges for High Energy Physicists 3

Throughout the history of quantum field theory there has been a rich cross-pollination between high energy and condensed matter physics. From the theory of renormalization to the consequences of spontaneous symmetry breaking, this interaction has been an incredibly fruitful one.

In the last decade there has been a strong resurgence of interest in condensed matter systems in the high energy theoretical physics community. Taking advantage of developments in conformal field theories, the conformal bootstrap, gauge/gravity and other type of dualities, as well as effective field theory techniques, high energy theorists with all kinds of specialist backgrounds are thinking about the diverse behavior exhibited in low energy physical systems.

Recent developments also employed quantum field theory ideas to improve our understanding of condensed and quantum matter systems as, for example, Femi liquids, strange metals or the behavior of topological defects in ultra cold atom gases. For certain questions, such approaches present relevant advantages with respect to more traditional techniques.

Moreover, in recent years the interplay between high energy and condensed matter physics found new fuel in the search for light dark matter. Indeed, theoretical analyses have recently shifted the attention towards model for sub-GeV dark matter. The condensed matter community has played a crucial role in the design of possible new materials and detectors that could allow the observation of such particles.

The aim of this workshop is to bring together like-minded high energy theorists with appropriate condensed matter theorists and experimentalists, to tackle some of the most interesting problems in modern physics. The format has been designed to allow for plenty of time for open discussion and interaction between the participants. This will reinvigorate existing collaborations as well as create new, fruitful ones.

It is well known that the dimension of conserved currents is determined
simply from dimensional analysis. However, a recent proposal is that what
is strange about the conserved currents in the strange metal in the
cuprate superconductors is that they carry anomalous dimensions. The
basic model invoked to exhibit such behaviour is a holographic dilatonic
one in which the field strength couples to the radial coordinate. I will
show that the anomalous dimension in such cases arises from a fractional

I will discuss recent discovery that elasticity theory of a two-dimensional crystal is dual to a fracton tensor gauge theory, providing a concrete manifestation of the fracton phenomenon in an ordinary solid. The topological defects of elasticity theory map onto charges of the tensor gauge theory, with disclinations and dislocations corresponding to fractons and dipoles, respectively. The transverse and longitudinal phonons of crystals map onto the two gapless gauge modes of the gauge theory. The restricted dynamics of fractons matches with constraints on the mobility of lattice defects.